In selecting a vacuum cleaner for home use, consumers today have many choices including a choice between an upright and a canister style vacuum cleaner, a choice between a bagged or a bag less dirt collection, and, a choice between a cyclonic versus a non-cyclonic cleaning action. Typically, two very important factors in the consumer's decision regarding the purchase of a vacuum cleaner are the ease of use of the vacuum cleaner and its cleaning effectiveness. Based on these factors, the bag less style of upright vacuum cleaner has become popular recently because it no longer requires the unpleasant task of periodically changing vacuum cleaner bags. Instead, the consumer merely removes the dust cup or container and empties it over a trash receptacle. Occasionally, the consumer must also clean out a removable filter within the dust cup that traps smaller particles of dirt. One of the problems associated with the task of emptying the dust cup is that the top of the dust cup is typically open to the air thus allowing that dust previously vacuumed, can be released back into the air during the process of transporting the dust cup to the trash receptacle.
Another feature of today's bagless vacuum cleaners is that the dust cup or container is typically made of clear plastic so that the operator can observe the cleaning action of the vacuum cleaner. This visual effect lets the operator monitor the effectiveness of the cleaning action and determine when the container should be emptied or the filter cleaned. Examples of such bagless upright vacuum cleaners can be found in U.S. Pat. Nos. 6,146,434; 6,070,291; and, 5,558,697. The problem with relying on this visual assessment of the cleaning action is that most consumers may not realize when the cleaning effectiveness has deteriorated by simply viewing the cleaning action. In fact, the cleaning effectiveness is also dependent upon the condition of any filtering devices disposed in the airflow path and if such filter is clogged or dirty, the cleaning effectiveness of the vacuum cleaner can be compromised without the operator being able to visually detect such condition. Accordingly, it would be beneficial if a bagless upright vacuum cleaner provided some additional means for determining the cleaning effectiveness particularly with respect to any filter devices that may be included with the bagless vacuum cleaner.
Of further importance in the operation of such bagless vacuum cleaners is the actual task of removing and reinstalling the dirt-collecting chamber so that the dirt can be emptied into a trash receptacle. Often times the operator has to make several attempts to align the dirt-collecting chamber properly for continued operation. It would be advantageous if the bagless vacuum cleaner included a simple and easy to use arrangement for aligning and reinstalling the dirt collecting chamber following a routine exercise of emptying the chamber.